The present invention concerns new 17-substituted steroids, a process for making them and methods of using them.
As is known, 11 .beta.-hydroxy steroids having anti-inflammatory activity (such as, for example, the corticoids: hydrocortisone, prednisolone, dexamethasone, betamethasone, prednylidene, triamcinolone, fluocinolone or flurandrenolone) are prepared by means of very expensive, multistage partial syntheses from naturally occurring steroids (such as diosgenin), whose procurement in adequate amounts is encountering increasing difficulties. Within the multistage syntheses of these compounds, the microbiological introduction of the 11 .beta.-hydroxy group into the steroid skeleton normally is the most costly and most wasteful step of the synthesis.
A process was developed in 1966, by which the yield of 11.beta.-hydroxylation of 11-deoxy-17.alpha.-hydroxy steroids of the pregnane series could be substantially increased. This process involves esterifying the 17 .alpha.-hydroxy group, then conducting a hydroxylation with the aid of fungi of the genus Curvularia, and saponifying the thus-obtained 11 .beta.-hydroxy-17.alpha.-acyloxy steroids (German Pat. No. 1,618,599=U.S. Pat. No. 3,530,038).
However, the acylation of the 17-hydroxy group is rather expensive; and the yields obtained thereby are frequently unsatisfactory.
The hydrolysis of the 11.beta.-hydroxy-17 .alpha.-acyloxy steroids is likewise difficult since by-products are frequently formed. This requires an expensive and wasteful purification of the thus-obtained products so that the latter will satisfy the purity criteria demanded of active medicinal agents.